Question

A golfer hits a ball. The ball leaves the club with an initial upward velocity of 40 meters per second. If the ball is 0.25 meters off the ground when it leaves the golf club, about how many seconds will it take for the ball to hit the ground?

Answer 1

h = -1/2 g t^2 + 40 t + .25

h = 0 , g = 9.8 m/s^2

solve for t
... quadratic formula works good
... you want the larger positive value